topic

All about meta tegakh

Meta tegi are used for the description of properties HTML of the document and should is in frameworks tega HEAD. If in the document it is used teg TITLE meta tegi it is recommended to insert into the document after him{it}.

Meta tegi have very wide functional orientation, but much is not standardized yet or is at a stage of development.

Meta tegi can identify authorship HTML of the document, his{its} address and as often he is updated. Search engines use meta tegi for indexation and formation of headings HTML of documents.

Meta tegi can influence a mode of display HTML of documents though on the screen are not deduced.

Further will be described meta tegi, accepted by the majority of service providers and programs for a network the Internet.

Meta tegi share on two groups: NAME and HTTP-EQUIV.

Meta tegi such as NAME contain the text information on the document, his{its} author and some recommendations for search machines. For example: Robots, Description, Keywords, Author, Copyright.

Meta tegi such as HTTP-EQUIV influence formation of heading of the document and define{determine} a mode of his{its} processing.

Group information meta tegov

These tegi are not reflected by browsers, but processed by some search machines. As a rule, there is no necessity to use these tegi simultaneously. In most cases enough one information tega, allowing to identify the author or an accessory{a belonging} of the document.

Teg Author should contain a name of the author if the site belongs to the organization, it is meaningful to use teg Copyright. The information necessarily should be quoted, for example:

In addition information tegi can contain attribute "Lang", specifying language on which value of property is written. An example:

Meta teg Description

Meta teg Description - serves for the brief description of a page.

He is used by search machines for indexation and as the brief summary at the link in the answer to search. And under the maintenance{contents} of it tega the user of the search engine will estimate, there corresponds{meets} your site to his{its} expectations whether or not.

If teg Description is absent, as the description search machines use the first line of the text or a fragment from the text with the found keyword.

It is desirable that the length of the description did not surpass 80 symbols. An example:

Meta teg Document-state

Meta teg Document-state - it is intended for management of indexation of search robots. Can have two values:

Static - there Is no necessity to index this page in the future.

Dynamic - To index this page on a regular basis (by default).

The mode "Static" is intended for pages which do not vary basically. If the maintenance{contents} of your page periodically varies to use this teg unessentially. An example:

Meta teg Generator

Meta teg Generator is only one of "nice{famous}" family tegov widely used by generators HTML of a code in the purposes. As a rule, for the owner of a site these tegi do not bear{carry} useful loading.

Meta teg Keywords

Meta teg Keywords is used by search machines for a rating of relevance.

The words contained in tege Keywords, are considered{examined} by search machines as the recommendation, but sometimes this drop does not suffice to move{weigh down} a bowl.

At formation of the list of keywords for meta tega Keywords it is necessary to use the words contained in the text of the document. The words which are not contained in the text, it is possible to use in very small amounts, two - three words. To insert them it is necessary in the end of the list.

Keywords should not will be repeated in tege Keywords, as a last resort, no more than two times.

In meta tege Keywords it is meaningful to use no more than 10 words, a lot of relevance will not increase.

In most cases search machines find the keywords worth in plural (cats) even if search is set in a singular (cat). Therefore it is recommended in teg Keywords to bring English nouns in plural.

Robots of some search machines do not pass to a new line at the analysis meta tega Keywords, therefore it is not recommended to break it{him} into some lines.

Example:

If the document is written in several languages, it is possible to use additional attribute lang for a choice of the coding (look the description meta tega Content-Language).

Example:

But it is more preferable to make separate pages, everyone in the language with transitions with one on another, with the help tegov <A> and <Link>.

Meta teg Resource-type

Meta teg Resource-type - describes a status of the given document. If his{its} value is distinct from "Document" search engines of it{him} will not index.

It is intended for use in large projects, with set of documents of different type.

Some possible{probable} values:

Build

Classification

Creation

Document - Is accepted by default.

Formatter

Host

Operator

Random text

Rating

Site-languages

Subject

Template

Version

Example:

Meta teg Revisit

Meta teg Revisit - specifies to the search robot, through how much days he needs to return and pereindeksirovat` the given document.

Example (to come once a week):

Meta teg Robots

Meta teg Robots - contains instructions{indications} for robots of the search machines collecting the information about HTML documents in a network.

Value of property Robots can consist of the following directives divided{shared} by points:

Index - this page should be indexed.

Noindex - this page should not be indexed.

Follow - to trace hyperlinks on page.

Nofollow - to not trace a hyperlink on page.

All - = index, follow (it is accepted by default).

None - = noindex, nofollow.

Teg <META name=Robots content = "all"> changes nothing in job of the robot of the search machine as value "all" is accepted by default.

But if this page is created dynamically or very much often is updated, there is no sense of her{it} to index, as the information on page in the search machine and its{her} true maintenance{contents} will be different.

In this case it is possible to recommend for the search machine to not index this page but only to trace on her hyperlinks, what proindeksirovat` other part of a site

At use tega, forbidding tracking of hyperlinks

The part of a site can remain not proindexed as inside a site robots move on gipersylkam. And those pages, transition on which it is blocked, will not be indexed.

Meta teg Robots has a priority above the directives of management set in a file robots.txt.

Meta teg Subject

Meta teg Subject is used by search machines for definition of subjects of the document. But until search engines will not coordinate classification tables, use of it tega is not always justified.

Meta teg URL

Meta teg URL - serves for exception of indexation of generated pages and mirrors. Having met this teg, the robot of the search machine should stop indexation of the current document and to proceed{pass} under the specified link. An example:

Meta teg Content-Language

Meta teg Content-Language is an instruction{indication} of language of the document. It is used by search machines at indexing. Though the majority of them are able to distinguish language under the text.

Some possible{probable} values (the standard [ISO639], [ISO3166]): de, el, en, en-GB, en-US, en-cockney, es, fr, it, i-navajo, ja, he, nl, ru, pt.

Example:

In specification HTML 4.0 there is an alternative opportunity of the obvious instruction{indication} of language - <html lang = "en">

Meta teg Content-Script-Type

Meta teg Content-Script-Type - Definition of the programming language of scripts.

Some from possible{probable} values: text/javascript, text/perlscript, text/tcl, text/vbscript.

Example:

If teg Content-Script-Type it is not used, type of the programming language of the scripts, distinct from accepted by default, the example should be specified directly in everyone tege <SCRIPT>,

In one document use of several programming languages of scripts is supposed. The instruction{indication} of language in tege <SCRIPT> has higher priority, within the framework of current tega <SCRIPT>.

Meta teg Content-Style-Type

Meta teg Content-Style-Type - ukazavaet language of the table of styles, value "text/css" is accepted by default if it arranges you also you do not use in this document tegi <Style> and <Span> to use this teg unessentially. An example:

Browsers define{determine} language of tables of styles on the following algorithm:

If in the announcement META is set language of tables of styles defines{determines} last announcement in a stream of symbols.

If language of tables of styles is set in announcement STILE, language of tables of styles defines{determines} last heading in a stream of symbols.

If language of tables of styles is not set, language "text/css" is by default used.

Meta teg Content-Type

Meta teg Content-Type - Is responsible for the instruction{indication} such as the document and codings of symbols.

To use meta teg Content-Type it is necessary only in view of some nuances.

In - the first, the coding of symbols of the text should correspond{meet} to the coding specified in tege.

In - the second, the server should not change the coding of the text at processing search of a browser.

? - the third if the server changes the coding of the text, he should correct or remove meta teg Content-Type.

Non-observance of these requirements can lead to to the following: the web-server will automatically define{determine} the coding of search of the client and will give a page to a web-browser recoded. The browser, in turn, will read the document according to meta tegom Content-Type. And if codings will not coincide to read the document it will be possible only after lines of intricate manipulations. Especially it is typical of old browsers IE 3.x - 4.x and Netscape 4.x.

Attention! Meta teg Content-Type very much often is inserted by generators HTML of a code.

Some codings from possible{probable} types (the standard [ISO10646]): Windows-1251, KOI8-r, ISO-8859-1.

Example:

Meta teg Expires

Meta tegi Expires - operates caching. If specified in tege date has passed, the browser should make repeated network search, instead of use a copy from a cache. If initially to name past date the document will not be kehshirovat`sja.

Some search robots can refuse to index the document with out-of-date date.

Date should be specified in the standard [RFC850].

Example:

Meta teg PICS-Label

Meta teg PICS-Label - (Platform-Independent Content rating Scheme Label)) defines{determines} a level of availability of a site (sex, violence), but can be used and in other purposes.

Meta teg Pragma

Pragma - the Control of caching. At value "no-cache" caching given is not recommended. It is intended for the documents received as a result of job of a script. An example:

Meta teg Refresh

Meta teg Refresh - definition of a delay of time in seconds after which a browser automatically updates the document. An additional opportunity - automatic loading of other document. An example:

If it is necessary to update simply the document URL to specify not necessarily.

Meta teg Set-Cookie

Set-Cookie - Adjustment cookie a browser.

Example:

<META HTTP-EQUIV = "Set-Cookie" content = " NAME=value;

EXPIRES=date; DOMAIN=domain_name; PATH=path; SECURE ">

Attributes EXPIRES, DOMAIN, PATH and SECURE if necessary it is possible to lower{omit}.

Example:

NAME - the Name cookie, cannot contain symbols of translation of a line, blanks, semicolons (;) and tabulation.

EXPIRES - the Storage time cookie. After the specified date (in a format " Wdy, DD-Mon-YYYY HH:MM:SS GMT ") the storage time cookie expires.

DOMAIN - the Domain for which value cookie is set. For domains COM, EDU, NET, ORG, GOV, MIL, INT it is possible to set value in abbreviated form "MY.COM", it will be distributed and to domain " WWW.MY.COM ". For all others (including RU) it is necessary to set value completely "WWW.MY.RU".

PATH - Establishes a subset of documents to which action cookie is distributed. At value "/doc" action cookie will be distributed on all files and catalogues in this directory beginning on "doc" (/doc/,/document/,/doc2/, docs.html, doc-test.htm).

If this attribute is lowered{omitted}, value cookie is distributed only to documents of a directory in which the current document is located.

SECURE - Specifies, that the information about cookie should is sent through HTTPS (HTTP with use SSL). Otherwise the information about cookie will be is sent under report HTTP.

Before search to the server, the browser checks cookie. And if attributes NAME, DOMAIN and PATH coincide, the browser sends cookie to the server.

If cookie accepts new value, old value leaves.

The browser has a number{line} of restrictions on job with cookie:

Lumpsum it can be stored{kept} no more than 300 values cookie.

Cookie cannot exceed 4 Kb.

From one server (domain) cannot be more than 20 cookie.

These restrictions can be a little bit others, depending on adjustment and such as a browser.

If there is an excess of a limit (the general{common} or on the domain) the first recording on time leaves. Removal{distance} occurs, is not dependent on value of attribute EXPIRES.

At excess of 4 Kb, cookie it is truncated.

Example:

<META HTTP-EQUIV = "Set-Cookie" content = " NAME=cookexample;

EXPIRES=Monday, 22-FEB-02 21:11:51 GMT; DOMAIN=WWW.MY.RU;

PATH =/; SECURE ">

Meta teg Window-target

Meta teg Window-target - defines{determines} a window of the current page. The resulted example can be used for the termination{discontinuance} of occurrence of new windows of a browser at application of frame structures. Operates for many (but not for all) browsers. An example: